1. Field of the Invention:
This invention relates to a vehicle lift of the type which is installed under the ground or floor. It is used for lifting a vehicle above the floor when repairing it.
2. Description of the Prior Art:
There are known underground vehicle lifts which are wholly installed in a pit, as disclosed, for example, in Japanese Utility Model Application Laid-Open No. 72495/1985 and Japanese Utility Model Application Laid-Open No. 145194/1985. They include jacks which are provided with upright cylinders and upright piston rods carrying a vehicle supporting table at their upper ends. The pit within which the upright cylinders can be completely accommodated has, however, a depth of at least, say, 2.5 m. The excavation of such a deep pit costs a great deal. The installation of the lift in such a pit is also a costly job and its maintenance is not an easy task, either.
There are also known lifts which are partly installed in a pit. One of the jacks is installed under the floor, while the other jack is situated on the floor. This type of jack also has a number of drawbacks. Its installation, including piping work, costs a great deal. If any leakage of a hydraulic fluid results from the breakage or corrosion of the piping, the piston in a cylinder is likely to drop suddenly and thereby cause a serious hazard to the operator. These kinds of trouble also create a very hard repair job.